View mmbt6428 datasheet:

MOTOROLA Order this document SEMICONDUCTOR TECHNICAL DATA by MMBT6428LT1/D Amplifier Transistors MMBT6428LT1 COLLECTOR NPN Silicon MMBT6429LT1 3 1 BASE 2 3 EMITTER MAXIMUM RATINGS 1 Rating Symbol 6428LT1 6429LT1 Unit 2 Collector–Emitter Voltage VCEO 50 45 Vdc CASE 318–08, STYLE 6 Collector–Base Voltage VCBO 60 55 Vdc SOT–23 (TO–236AB) Emitter–Base Voltage VEBO 6.0 Vdc Collector Current — Continuous IC 200 mAdc THERMAL CHARACTERISTICS Characteristic Symbol Max Unit Total Device Dissipation FR–5 Board(1) PD 225 mW TA = 25°C Derate above 25°C 1.8 mW/°C Thermal Resistance, Junction to Ambient RqJA 556 °C/W Total Device Dissipation PD 300 mW Alumina Substrate,(2) TA = 25°C Derate above 25°C 2.4 mW/°C Thermal Resistance, Junction to Ambient RqJA 417 °C/W Juncti